Add galleries to homepage posts in Mindstream

functions.php

// Add galleries to posts on the homepage if they have them
add_action( 'genesis_post_content', 'sp_gallery_in_excerpt', 1 );
function sp_gallery_in_excerpt() {
    if ( !is_home() && !is_front_page() )
        return;

    if ( get_post_gallery() )
        echo get_post_gallery();
}